GENEVA • The release of a United Nations report detailing the massacre of thousands of civilians by Rwandan and Congolese forces in the Democratic Republic of Congo has been delayed by a month, U.N. human rights chief Navi Pillay said Thursday.

The draft report, leaked to the media last week, outraged Rwanda and led the East African nation to threaten to pull its troops from U.N. peacekeeping missions.

"Following requests, we have decided to give concerned states a further month to comment on the draft," Pillay said, "and I have offered to publish any such comments alongside the report itself on 1 October, if they so wish."

The report details the killings of tens of thousands of noncombatants, in the Democratic Republic of Congo between 1993 and 2003.

According to the report, the Rwandan army and associated Congolese rebel groups systematically targeted members of the Hutu tribe.

Hutu militia slaughtered 800,000 ethnic Tutsis and moderate Hutus during Rwanda's 1994 genocide, which was ended by invading Tutsi forces led by Paul Kagame, who is now president of the Central African nation. About 1 million Hutus fled to the Democratic Republic of Congo.

The actions of the Rwandan army could be defined as genocide, the report said.